Mr Leach is believed to have paid the price for last week's warning that the television company has fallen into loss.
Yorkshire's non-executive directors met in London on Friday to decide how to respond.
Contrary to reports at the weekend, it was suggested yesterday that Allan Hardy, commercial director, will keep his job.
Yorkshire's latest difficulties came to a head after it handed over the job of advertising sales to a subsidiary of London Weekend Television. LWT Holdings owns a 14 per cent stake in Yorkshire and Greg Dyke, LWT's chief executive, is a director of Yorkshire.
Media & Airtime Sales, Yorkshire's advertising sales arm, had previously sold airtime in advance in an effort to book the income for the group's 1992- 93 financial year, which ended on 30 September.
But LWT refused to allow this practice, which Yorkshire claims is not unusual in the television industry. The consequent shortfall in advertising revenue has produced a loss estimated at up to pounds 20m.
Pearson, the media group that owns the Financial Times, was also unhappy with Yorkshire's performance under Mr Leach.
Suggested replacements as an interim chairman include Ward Thomas, a Yorkshire director who was previously managing director of Yorkshire Television, and Dennis Stevenson, the well-regarded chairman of GPA, the Irish aircraft leasing group.
LWT would not comment yesterday.Reuse content